SOLUTION: how do i solve y=2x; x+2y=8 using substitution?

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Question 177054: how do i solve y=2x; x+2y=8 using substitution?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
Take the expression for y given by your first equation and substitute (hence the name of the method) that expression in x for y in the second equation, like this:

y+=+2x

x+%2B+2y+=+8 therefore x+%2B+2%282x%29+=+8 => 5x+=+8 => x+=+8%2F5

Substitute (there's that word again) this value you determined for x back into the first equation, thus:

y+=+2%288%2F5%29+=+16%2F5